Pivot polisher



May 1, 1945.

V. L. EMANUEL- PIVOT POLISHER Filed Sept. 28, 1942 Mezz/02,

Patentedv May 1, 194,5

UNITED STATESPATENT l(nancy, l

PIVOT PLISHER `f Victor L. Emanuel, Dubuque, Iowa` Application September 28, 1942, Serial No. 460,036

rc1. :i2- 6) 2 claims.

My invention relates to a device for suitably holding and rotating the balance wheels of watches for polishing and straightening the pivots of the wheels; the invention having for its object the provision of a device whereby the balance wheel may be given continuous rotation at any desired controllable speed through the ymedium of power driven mechanism `while both hands of the operator are left free for the pivot polishing or pivot straightening operations.

The invention also has for its object the provision of a device which is adapted to balance wheels of various widths and sizes or balancewheel arrns length; and wherein the bearing for the balance wheel pivot is readily replaceable without need for discarding or replacing the rotatable shaft necessitated by the fact that the pivot receiving socket in the end of the pulley carrying sha-ft has become Worn.

The invention also contemplates a device wherein the exposed pivot is held by a thin and slidably adjustable free-plate which may also be readily replaced should occasion require.

The foregoing enumerated objects and advantages, as well as other advantages inherent in the invention, will all be readily comprehended from the detailed description of the accompanying drawing wherein- Figure 1 is an end elevation of a Watchmakers lathe with my invention applied thereto and showing a watch balance wheel mountedtherein.'

Figure 2 is a side elevation of lmy improved balance wheel holding device removed from ther lathe and shown enlarged with one of the pivot bearings in section and the mounting post broken away.

Figure 3 is a detail sectional view taken on-the line 3 3 of Figure 2 and looking in the direction of the arrows.

Figure 4 is a sectional plan View taken on the line 4-4 of Figure 2 as indicated by the arrows.

Figure 5 is a detail perspective view oftheadjustable pivot bearing bracket. i p

Figure 6 illustrates, in perspective, Va pulley and chuck for securing the pulley to the main pulley` shaft.

In the exemplication of the invention, my improved balance wheel pivot polisher is shown applied to a watchmakers lathe `in Figure l, provided wth the usual` pedestal IIJ and the horizontally disposed bed II provided in its upper face with the usual T-shape slot for mounting the member I2 which rotatably supports a shaft on which the stepped pulley I3 is secured. 1 I

The end of the main pulley shaft has a tapped` -socket adapted to" receive the threaded end of the lathe-chuck M which receives and grips the spindle of the small pulley I5, thus causing the pulley I5 to rotate with `the main pulley; the method of construction and mounting enabling ready application and removal of the driving mechanism of my improved polisher to a jewelers lathe. l

My invention involves a base bracket IE adapted to be suitably supported by an extension of the "If-'stock I'I whichis secured on the lathe bed- I I, by the threaded post and clamp screw shown at IIR. The bracket I6, at one end, is provided with a depending post I8 which fits into a chucklike opening in the T-stock extension.` One end of the bracket is bent upwardly; the upwardly disposed end I 5a supporting a stub shaft on which a grooved pulley I9 is rotatably mounted and the inner end of the shaft is provided with a-socket to receive the end, or a stud on the end, of a cone bearing 20 which is apertured at the apex orl tip and is preferably held in place by a ferrule or sleeve ZI which in turn may be secured to the shaft in any suitable manner, as for example by small set-screws. Slidably mounted in a transverse hole in the grooved pulley I9 is a crank-arm 22 whose free end is adapted to engage `the balance Wheel W and impart rotative `movement thereto.

The crank arm" is `slidable in the pulley and may thus be `easily adjusted to various sized balance wheels or wheel arm lengths.

In polishers as heretofore constructed the balance wheel was controlled by affork` made to graspthe balance wheel on opposite sides and which therefore has to be adjusted to various width of balancewheel arms. `These forks are rather delicate in construction and more or less difficult to make,requiring timein construction and adjustment and replacement or substitution.

`My improved means for imparting rotation to the balance wheels obviates the `need for delicate ladjustment. and eliminates the time and expense involved `in the fork construction; the simple crank-arm may be easily constructed and applied and as apparent, is adapted to any size of balance Wheelby merely sliding the crank-arm in or out of its hole in the pulley I 9. I I

l In order to prevent the accidental `in-and-out l or sliding movement of the crank-arm, I provide `the side of the pulley I9 with a spring strip 23 whose base is arranged at right angles and is removably secured to the pulley by the screws 24,

see Figure 3, with the free end of the `spring ar` ranged in frictional contact with the side of the crank-arm 22.

Adjustably mounted on the base bracket I6 is a pivot holding angular bracket 25 which, at a point in axial alignment with the cone bearing 28, is -provided with a small hole of predetermined size, at 26, to receive the pivot point P at one end of the stai of the balance wheel W; the hole 26 being of size sufficient to permit the pivot point P to extend suiflciently therethrough to be polished and straightened when necessary. The base portion of the pivot supporting bracket 25 at prearranged points is provided with holes to receive the upstanding pins 21, 2'I of a base plate 28 whose one end is bent upwardly as shown at 29.

The pins 21, 2l being spaced apart as shown prevent pivot bracket 25 twisting or turning horizontally; the pivot bracket 25 and the base plate 28 are both apertured to receive the clamp-screw S which is adapted to clamp the bracket and base plate in the adjusted positions on the main bracket or frame I6 which issecured to the T- stock extension. The base plate 28 also is provided With a pair of downwardly disposed pins 30, 30 which extend into a longitudinal slot 3I in the main bracket or frame I8 and permit the bracket 25 and plate 28 to be adjusted longitudinally when the clamp-screw S is released; the desired accurate adjustment of the superposed bracket 25 and base plate 28 being accomplished, before clampscrew S is screwed down, by the thumb-screw 32 which extends through a tapped hole in the small upstanding post 33 which is riveted to the frame I6.

The balance wheel rotating mechanism is actuated by means of a small rubber transmission belt or friction band 34 which passes about pulley I9 and is driven by pulley I 5.

When pulley I9 is driven by the rubber band or friction belt 34, the balance wheel W (which has previously been mounted in place) will be rotated continuously in the same direction as pulley I9 through the medium of the crank-arm 22. It will be understood that before power is imparted to the pulley I3, the balance wheel to be polished or operated on is first mounted in place by supporting one end of the balance wheel staff in the cone bearing 28, adjusting or moving the bracket 25, lengthwisely of the main bracket; or frame I6 to permit the balance wheel pivot P to properly extend through the aperture 26 in bracket 25 in order that the pivot may be straightened, if need be, and polished, After the balance wheel has been mounted as described, the bracket 25 and its adjusting plate 28 are held in adjusted position by screwing screw 32 into abutting relation with the upturned end of the adjusting or base plate 28. The balance wheel pivot holding bracket is then clamped in place by clamp-screw and nut S; the proper spaced relation between the cone-bearing and the pivot receiving bracket being maintained by the thumb-screw 32 bearing against the member 28, as shown in Figure 2. The crank-arm 22 is then moved linto or out of the pulley I9 to such an extent that the free or crank end of the arm 22 will be in proper contact with the balance wheel and impart the rotative movement of the pulley I9 to the balance wheel; the crank-arm readily being adjustable to the size of balance wheel to be operated on, and its adjusted position being automatically maintained by the friction spring 23.

. As is aparent, the crank arm adapts itself to any size balance wheel and eliminates the use of the usual fork (a rather delicate thing to make) heretofore employed and which was made to grasp the balance wheel on both sides and hence required time and care in adjusting the same to balance wheels of different widths.

The pulley I9 preferably is driven as heretofore described, but it is apparent that gears may be employed instead of pulleys I5 and I9; either method imparting continuous rotation to the balance wheel in one direction, while the speed of rotation may be subject to control as for example by means of a foot operated rheostat or other well known means.

Pivot polishers as heretofore constructed and employed were operated by means of a bow-drive held in one hand of the operator and reciprocated or moved back-and-forth, causing the balance wheel to be alternatively rotated in opposite d1- rections. With this method of operation, only one hand of the operator is free for the work in hand and in the event of a bent balance pivot it is quite difficult to stop the balance wheel rotation at the desired point and to maintain the proper position of the balance wheel for a sufficient period of time to make the correction.

The old type pivot polisher is mounted by the repair man between the jaws of a small jewelers vise, where it is too low for comfort or convenience of the watchmaker, whereas my improved polisher is disposed at a high level, namely above the workers bench and hence closer to eye-level. Then too, with my improved polisher both hands of' the operator are free thereby eliminating the distraction resulting from the simultaneous use of both hands for operations of a dissimilar nature, namely one hand moving back-and-worth to impart rotation to the balance wheel while the other hand is employed in making correction or in performing the desired operation on the balance-wheel,

My improved pivot polisher is constructed to be easily and quickly mounted on the T-stock of a jewelers lathe and likewise may be readily removed without inconvenience or loss of time, thus enabling the device to be operated by a motor through the medium of the usual motor driven pulley of the lathe. The invention provides a simple and durable means for effecting operative relation between the pulley and the balance wheel and also provides a left-bearing which may be easily removed and replaced thereby prolonging the life of the tool indenitely. With the bearing mounted in a recess or socket in the exposed end of the pulley shaft, the bearing may be accurately centered and held; the construction at the same time aiiording a simple and accurate method of center-punching the slidable pivot holding bracket in preparation for drilling the hole in a new pivot holding bracket.

In order to provide a long and more durable threaded support for the adjusting thumb-screw 32, I prefer to provide the supporting bracket or frame I8 with the upstanding post 33 which has a tapped opening therethrough for the thumbscrew 32. 'I'his post 33 is rather small so as not to interfere with the balance wheel pivot operations.

The exemplication shown and described is believed to be the best embodiment of the invention, but structural modifications may be possible without, however, departing from the spirit of the invention as dened in the appended claims,

What I claim is:

1. A balance wheel pivot polisher comprising, in combination with a jewelers lathe provided with a power driven pulley shaft, a T-stock with a lateral extension and a supplemental pulley removably secured to said shaft, a horizontally disposed supporting frame removably mounted on said T-stock extension, extending lengthwise of the lathe out of alignment and parallel with the power shaft and having an upstanding end provided with a non-rotating stub-shaft socketed at its free end, a pulley loosely mounted on the stub-` shaft and provided with an adjustable balance wheel engaging arm slidable in said pulley, an apertured cone bearing removably mounted in the stub-shaft socket, an upstanding apertured pivot receiving member horizontally slidable on said supporting frame, means whereby saidmember is held in alignment with the cone-bearing aperture, and adjusting means mounted on the supporting frame whereby the position of said pivot receiving member relative to said cone bearing may be determined,

2. A balance wheel pivot polisher comprising,

in combination with a jewelers lathe provided with a power driven shaft having a lathe-chuck tapped in its end, a pulley removably held by the chuck to rotate with said shaft and a T-stock provided with a laterally disposed extension; a separate unit composed of a horizontally disposed supporting frame removably mounted on said extension and extending out of alignment and parallel with the power shaft, said frame i having a longitudinal slot and an upstanding end provided with a non-'rotating 'stub-shaft with a pulley loosely mounted thereon; a balance wheel controlling member slidably held by said last mentioned pulley; resilient means secured to the side of said pulley for frictionally holding said member; an apertured cone bearing removably secured to the end of said stub-shaft in axial aligni ate the last mentioned end of said bracket and `the slot in said supporting frame whereby the bracket is maintained in alignment with the longitudinal axis of said supporting frame; and regulable means operatively disposed intermediate the bracket and the supporting frame whereby longitudinal adjustment of said bracket on the supporting frame may be controlled.

VICTOR L. EMANUEL. 

